Magnetic anisotropy in arc-cast Nd-Fe-B-Zr alloys

Author

Fujita, A. ; Harris, I.R.

Author_Institution

Sch. of Metall. & Mater., Birmingham Univ., AL, USA

Volume

29

Issue

6

fYear

1993

fDate

11/1/1993 12:00:00 AM

Firstpage

2803

Lastpage

2805

Abstract

Magnetically anisotropic ingots with composition of (Nd_2.2Fe₁₄B)_100-x Zr_x are prepared using an arc-melting furnace. The direction perpendicular to the cooling surface is found to be magnetically hard compared with the parallel direction. The c-axis of each grain is considered to be distributed randomly in the plane parallel to the cooling surface. Zr addition reduces the amount of iron dendrites and makes the anisotropic feature more distinct. After annealing at 1040°C for 24 hours, very little grain growth in Zr containing ingots is observed in contrast with Zr-free ingots. The HDDR (hydrogenation, disproportionation, desorption and recombination) treatment of these ingots shows that higher Zr addition cause a coercivity decrease. The anisotropy features are partially preserved after recombination, but only in the annealed ingot

Keywords

annealing; boron alloys; coercive force; dendrites; desorption; ferromagnetic properties of substances; grain growth; iron alloys; magnetic anisotropy; neodymium alloys; permanent magnets; zirconium alloys; (Nd_2.2Fe₁₄B)_100-x Zr_x; 1040 degC; 24 hours; HDDR; annealing; arc-cast Nd-Fe-B-Zr alloys; c-axis; coercivity decrease; dendrites; desorption; disproportionation; grain growth; hydrogenation; magnetic anisotropy; magnetically hard magnet; recombination; Anisotropic magnetoresistance; Annealing; Cooling; Furnaces; Iron; Magnetic anisotropy; Neodymium; Perpendicular magnetic anisotropy; Surface treatment; Zirconium;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.281058

Filename

281058